EP0496104B1 - Sanitary mixing valve - Google Patents

Abstract

An electrically operated sanitary mixer tap system comprises a hollow piston (17) for adjusting the temperature, which in particular may be a rotary piston. The hollow piston (17) moves in a chamber (21) of the housing (1) of the mixer tap system, into which the flow paths (22, 23) for cold and hot water open. A particular structure (27) on the outside of the hollow piston (17) cooperates with the openings of the flow paths (23, 27) and thus determines the mixing ratio of the mixed water flowing out of the fitting. Its further path to the outlet of the sanitary fitting leads at least in regions through the interior of the hollow piston (17). Located at this point are (at least) the closing members (30, 34) of an electrically operated valve, which in this way controls the flow of mixed water to the outlet of the fitting. This arrangement of the closing members (30, 34) radially inside the hollow piston (17) facilitates a particularly space-saving construction (FIG. 4).

Description

The invention relates to a sanitary mixer tap with a housing, with an electrically operated valve, the closing elements of which control the outflowing mixed water, with a control element arranged in a chamber of the housing, which determines the ratio of cold and hot water in the outflowing mixed water, and with an outlet .

A problem with all such known electrically operated sanitary fittings e.g. JP-A-1203530, especially in the case of non-contact controlled sanitary fittings, is the space required by the mechanical and electrical components. If all these components are to be combined within the sanitary fitting, the result is often a chunky, unsightly appearance. This is particularly true when the electrically operated sanitary fitting is a mixer tap, in which a control element for setting the mixing ratio of cold and hot water must also be provided.

In known sanitary mixer taps of the type mentioned at the outset, the control element determining the mixed water temperature and the electrically operated valve (generally a purely shut-off valve) were spatially separated from one another.

The object of the present invention is to design a sanitary mixer tap of the type mentioned at the outset in such a way that at least the control element and the electrically operated valve require less space and the mixer tap can thus be given a more pleasing appearance.

• a) das Regelelement als Hohlkolben ausgebildet ist;
• b) der Kohlkolben an seinem Außenumfang eine Struktur aufweist, welche im Zusammenwirken mit in die Gehäusekammer mündenden Strömungswegen für Kalt- und Warmwasser deren Mischungsverhältnis bestimmt;
• c) der Weg des Mischwassers zumindest teilweise durch den Innenraum des Hohlkolbens führt und in diesem Bereich des Innenraumes des Hohlkolbens zumindest die Schließelemente des elektrisch betätigten Ventils angeordnet sind.

This object is achieved in that

• a) the control element is designed as a hollow piston;
• b) the cabbage piston has a structure on its outer circumference which, in cooperation with flow paths leading into the housing chamber, determines the mixing ratio for cold and hot water;
• c) the path of the mixed water leads at least partially through the interior of the hollow piston and in this area of the interior of the hollow piston at least the closing elements of the electrically operated valve are arranged.

According to the invention, at least the closing elements of the electrically operated valve are therefore accommodated within the control element itself, which is designed as a hollow piston for this purpose. For this purpose, a water flow must be selected in which the path of the mixed water in the direction of the valve outlet at least partially leads through the interior of the hollow piston. In this way, the closing elements of the electrically operated valve take part in all movements of the hollow piston. The mutual nesting of control element and closing elements of the electrically operated valve not only saves considerable space; the result is a structural unit in which all mechanical elements of the sanitary mixer tap are combined, which can therefore be removed as a unit from the sanitary mixer tap and, if necessary, serviced or even replaced.

A cylindrical apron is expediently formed on the hollow piston, on which an actuating handle can be fastened. In general, it is still common Even with electrically operated or non-contact controlled sanitary fittings, the temperature is set manually.

With this configuration, the space surrounded by the apron can still be used meaningfully: namely, electrically operated valves generally comprise a solenoid. According to a special feature of the invention, this can be arranged in the space surrounded by the skirt of the hollow piston.

The structure on the outer circumference of the hollow piston, which determines the mixing ratio of the outflowing water, can in particular comprise a groove which guides the mixed water along the outside of the hollow piston. After entering the housing chamber in which the hollow piston moves, the water path first leads along the outside of the hollow piston before the mixed water is then conducted into the interior of the hollow piston and to the closing elements of the electrically operated valve arranged there.

It is easiest if the groove leads the mixed water to the open end of the hollow piston.

The control element is very often designed as a rotary piston. Then the configuration is recommended in which the groove is guided in a helical manner along the outer circumference of the hollow piston at an angle with respect to the axis and in which the center points of the mouth openings of the flow paths for cold and hot water into the housing chamber lie on a straight line that is to the axis of rotation of the hollow piston is parallel. The "oblique" groove cuts the two mouth openings of the flow paths for cold and hot water differently depending on the rotational position at. This means that depending on the rotational position, different amounts of cold and hot water can flow from the corresponding flow paths into the groove and from there into the interior of the hollow piston.

In general, pilot-operated valves are used as electrically operated valves for energy reasons. As a closing element, these comprise an elastic membrane which can move back and forth between an open and a closed position under the influence of the pressures prevailing on their two sides, a closing body which can be moved by the magnetic coil opening and closing a pilot opening reducing the pressures on both Affects sides of the membrane. Such a pilot-controlled valve can be used for the purposes of the invention in particular when the closing body and pilot opening are arranged away from the membrane in the vicinity of the magnetic coil, a first channel being led from the pilot opening through a massive area of the hollow piston into a room, in which the pressure prevailing on one side of the membrane is present, and from the space which comes into contact with the first channel after the closing body has been lifted off the pilot opening, a second channel is led into a space through a massive region of the hollow piston which is the pressure prevailing on the other side of the membrane. Due to the spatial separation of the elastic membrane and the closing body and the pilot opening, the spatial conditions on or in the hollow piston can be better utilized, the two channels mentioned serving to convey the pressures prevailing on both sides of the membrane.

• a) eine schlauchförmige, elastische Membran, die an ihren Enden an der Innenwand des Hohlkolbens festgelegt und im mittleren Bereich radial beweglich ist;
• b) ein innerhalb der schlauchförmigen, elastischen Membran angeordneter Anlagekörper, an dessen Mantelfläche die Membran in der Schließstellung anliegt und von dessen Mantelfläche die Membran in der Öffnungsstellung abhebt.

The embodiment of the invention in which the closing elements of the electrically actuated valve comprise:

• a) a tubular, elastic membrane, which is fixed at its ends to the inner wall of the hollow piston and is radially movable in the central region;
• b) an abutment body arranged within the tubular, elastic membrane, on the outer surface of which the membrane rests in the closed position and on the outer surface of which the membrane lifts in the open position.

The contact body is preferably part of a cage holding the membrane, which at the axial ends each has a support ring which interacts with a radial bead on the corresponding axial end of the membrane, the two support rings being connected to the contact body via ribs. In this way, the closing elements of the electrically operated valve are combined to form a unit which can be pushed into the interior of the hollow piston. This unit can also be replaced as a whole if necessary.

Figur 1:

die Vorderansicht einer berührungslos gesteuerten Sanitärarmatur;

Figur 2:

einen Schnitt gemäß Linie II-II von Figur 1;

Figur 3:

einen Schnitt gemäß Linie III-III von Figur 1;

Figur 4:

einen Ausschnitt aus Figur 3 in größerem Maßstab;

Figur 5:

eine Ansicht, ähnlich der Figur 4, jedoch geschnitten gemäß Pfeil V in Figur 2 (Drehkolben nicht geschnitten);

Figur 6:

einen Schnitt gemäß Linie VI-VI von Figur 3 in vergrößertem Maßstab.

An embodiment of the invention is explained below with reference to the drawing; show it

Figure 1:

the front view of a non-contact controlled sanitary fitting;

Figure 2:

a section along line II-II of Figure 1;

Figure 3:

a section along line III-III of Figure 1;

Figure 4:

a section of Figure 3 on a larger scale;

Figure 5:

a view similar to Figure 4, but cut according to arrow V in Figure 2 (rotary piston not cut);

Figure 6:

a section along line VI-VI of Figure 3 on an enlarged scale.

As can be seen in FIG. 1 of the drawing, the non-contact controlled sanitary fitting shown can be divided into five main components:

A swivel spout 3 is attached to a central main housing 1, to which a base part 2 is attached at the bottom. Inlet channels 4 for hot and cold water (one indicated by dashed lines in FIG. 2) penetrate the base part 2. Flexible water supply hoses 5 are screwed into these from below.

Symmetrical to the sectional plane II-II indicated in FIG. 1, two handle-like extensions 6 and 7 are attached to the main housing 1.

The left handle-like extension 6 has only the external appearance, but not the function of a handle. It is only used to hold the electronic components of the non-contact valve. 1 and 3 show the optical entry and exit window 8 for the infrared light used to detect a user. The window 8 is colored dark, so that its function as an optical window and the transmitter diode 9 behind it and the receiver diode 10 cannot be seen (see the section in FIG. 3). In FIG. 3 it can be seen how the electronics 11 are accommodated inside the handle-like extension 6, which is supplied with the supply voltage via a cable 12 on the one hand and which is connected to a solenoid valve 14 via a further cable 13 in a manner to be described which controls the flow of water. The cable 12 is made via an axially parallel bore 15 in the main housing 1 or the base part 2 and an oblique bore 16 in the main housing 1 from the sanitary fitting.

The arrangement is obviously such that in the handle-like approach 6 all those components are combined into one unit, which can be described as "electronic" in the sense that they serve the electrical detection of a user before the sanitary fitting and the generation of such signals with which a solenoid valve can be controlled.

The right handle-like approach 7 is not only "handle-like" in the illustrated embodiment, so it not only sees a conventional sanitary fitting handle but actually has this function. It can be rotated about its horizontal axis to adjust the temperature of the mixed water flowing out of the sanitary fitting. In the case of a sanitary fitting which only releases water at a single temperature, the attachment 7 would also only be "similar" to the handle, ie it would not really perform the function of a handle, but only pretend the presence of such a handle.

In the handle-like approach 7 all those components are housed or assembled as a unit, which serve to control the water flow and can be regarded as "mechanical" in this sense. These mechanical components include, in particular, a magnetically actuated pilot valve, the construction of which is explained in more detail below, and a rotary piston 17, also referred to as a "piston", for adjusting the temperature.

For a more detailed description of what is accommodated in or on the handle-like extension 7, reference is now made to FIGS. 4 and 5, which have a larger scale than FIGS. 1 to 3. The cup-shaped outer housing 18 of the handle-like extension 7 has been omitted in FIGS. 4 and 5 for the sake of clarity. It is fastened with a screw 19 to a cylindrical skirt 20 of the grater 17, as can be seen in FIG. 3. When the outer housing 18 is rotated, the entire grater 17 is taken along, which changes the mixing ratio of cold and hot water in a manner to be described.

The grater 17 is a one-piece molded part, which protrudes into a cylindrical chamber 21 of the main housing 1 at the end facing away from the apron 20. Bores 22, 23 (see also FIG. 5) which pass obliquely through the main housing 1 open into this chamber 21 and communicate with the bores 4 in the base part 2 and through which cold and hot water can thus reach the cylindrical chamber 21. Axially offset from the bores 22 and 23, another bore 24 of the main housing 1 opens into the cylindrical chamber 21, which is connected to a vertical bore 25 leading to the outlet 3. This can be seen in particular in FIG. 3. If the inner end of the grater 17 were not inserted into the cylindrical chamber 21, the water flowing in via the hoses 5, the channels 4, 22 and 23 into the cylindrical chamber 21 of the main housing 1 could directly flow through the bores 24 and 25 to the outlet 3 stream.

The setting of the mixing ratio of cold and hot water is done by an essentially cylindrical head 26 of the grater 17, in which an oblique groove 27 is incorporated. The groove 27 cuts channels 22 and 23 in the main housing differ depending on the rotary position. FIG. 5 shows the position in which the same proportions of cold and hot water are obtained because the channels 22 and 23 both open to the same extent, namely half, into the groove 27. Water can therefore flow into the groove 27 from the channels 22 and 23. The groove 27 guides the mixing water into a recess 28 on the outer circumference of the head 26 of the grater 17, from where it can reach the end of the grater 17.

An elastic cushion 79 is embedded in the lower region of the outer surface of the grater head 26. If the grater 17 is turned to the full cold position, the cushion 79 lies over the mouth of the bore 22 supplying the hot water and closes it tightly. This prevents hot water losses.

The further path of the mixed water arriving at the open end face of the grater 17 to the channel 24 and thus to the outlet 3 leads via the interior of the hollow head 26 of the grater 17, in which a pilot-controlled valve 29 is accommodated, and via a radial bore 44 in the grater 17 and an annular space 78, which lies between the wall of the chamber 21 and a reduced diameter area of the grater 17. The annular space 78 is delimited in the axial direction by two O-rings 56 and 57, which are arranged in grooves on the outer surface of the grater 17.

Without the pilot-controlled valve 29, the water arriving at the inner end face of the head 26 of the grater 17 could flow freely through the interior of the grater 17 to the channel 24.

The pilot-controlled valve 29 comprises a membrane 30 made of elastic material and a cage as closing elements 31 made of rigid plastic, with which the membrane 30 cooperates. Although this is shown in one piece in the drawing, it can also be constructed in several parts.

The elastic membrane 30 has the shape of two truncated cones, which are arranged in opposite directions, with beads 32, 33 projecting radially inwards on the axially opposite ends.

The cage 31 comprises a central contact body 34 and at both axial ends a support ring 35 or 36, which cooperates with the bead 32, 33 of the elastic membrane 30 located there. The contact body 34 of the cage 31 is connected via ribs 37 to the support rings 35, 36 to form a unit.

Cage 31 and membrane 30 tied thereon lie against a step in the interior of the grater and are releasably secured at the outer end by an insert ring 46 and a snap ring 47.

The elastic membrane 30 is shaped such that it normally rests against the outside of the contact body 34 of the cage 31, ie without pressure from water from inside or outside. This is the closed state of the pilot-controlled valve 29, since the water path through the interior of the grater 17 to the channel 24 is then blocked by the contact body 34 and the membrane 29.

The membrane 29 can move from the closed position shown into an open position by being raised in the central region from the contact body 34 and resting against the wall of the cylindrical chamber 21 of the main housing 1. An annular space between the membrane 29 and the contact body 24 is released for flow.

This movement of the membrane 30 occurs under the influence of the pressures that exist radially inside and radially outside of it. These processes are known per se and do not need to be explained in more detail here. In the present context, it is sufficient to know the following:

The inner space of the membrane 29 below the contact body 34 is connected to the outer space by a small radial compensating bore 38. This in turn communicates via an axially parallel channel 39 with a recess 40 on the outer, radially inside the apron 20 end face of the grater 17. The recess 40 is covered by the underside of the magnet coil 14 and sealed by an O-ring 45. At the bottom of the recess 40, a valve seat 41 is formed, which cooperates with a closing body 42. The closing body 42 normally closes the valve seat 41 and thus the access to an axially parallel channel 43, which leads to the radial bore 44 in the grater 17 and thus to the channel 24 in the main housing 1.

As long as the closing body 42 closes the valve seat 41, as shown in FIG. 4, the pressure force acting on the elastic membrane 30 from the outside is greater than the resulting pressure force prevailing in the interior of the membrane 29. The membrane 30 therefore remains in contact with the outer circumference of the contact body 34 of the cage 31; the pilot-controlled valve 29 is closed.

However, when the coil 14 of the pilot-controlled valve is energized, the closing body 42 lifts off the valve seat 41. This results in a change in the pressures acting on the membrane 30 in the sense that the membrane 30 in the middle region lifts off the contact body 34 and moves into the open position in which it rests on the inner wall of the head 26 of the grater 17 2.

When assembling the non-contact controlled sanitary fitting, the units held or formed by the handle-like extensions 6 and 7 are preassembled.

For the handle-like approach 6, this means that the transmitter diode 9 and the receive diode 10 and the electronics 11 are inserted and fastened into the housing 52 from the open end. The housing 52 has a thread at its open end, into which a ring 49 is screwed. Two screws 50, 51 (see also FIG. 2) extend transversely through the main housing 1 and are screwed with their threaded end into threaded bores in the ring 49. The heads of the screws 50, 51 lie against countersinking in the right side surface of the main housing 1 in FIG. 1. The left handle-like extension 6 is thus attached to the main housing 1. By using the ring 49 and the screws 50, 51, it is possible to precisely define the angular orientation of the housing 52 and thus the orientation of the optical window 8, which would not be readily possible if the housing 52 of the left handle-like extension 6 were simply included the end would be screwed into the main housing 1.

Before the final definition of the handle-like extension 6 on the main housing 1, the cable 12 is of course still run through the channels 15 and 16; the cable 13 is passed through a channel 53 which completely penetrates the main housing 1 (cf. also FIG. 2) to the other side surface of the main housing 1.

A cylindrical collar 54 at the inner end of the housing 52 protrudes into a groove on the left side surface of the main housing 1 in FIG. 1. This results in an optically pleasing transition between the handle-like extension 6 and the main housing 1.

The attachment of the handle-like extension 7 on the right in FIG. 1, which is actually a real handle, takes place in the following manner (the following description makes particular reference to FIGS. 3 to 6):

The grater 17 is provided with a groove 58 at that axial point at which the right-hand side face of the main housing 1 comes to rest in the installed state. A U-shaped fastening part 59 is inserted into this groove 58 from the side. This is screwed onto the right side surface of the main housing 1 in FIG. 1 with three screws 60, 61 and 62. One of these screws, namely screw 60, is shown in FIGS. 4 and 5; all three screws can be seen in Figure 6, which represents a section along line VI-VI of Figure 3, at the level of the heads of the screws 60, 61, 62. The heads of the screws 60, 61, 62 are accessible through recesses 63, 64, which extend axially parallel through the outer part of the 17 to the right end in FIG. 1. These recesses 63, 64 can alternately be brought into alignment with the heads of the screws 60, 61, 62 by turning the grater 17, so that the screws 60, 61, 62 can be inserted here and tightened with a screwdriver.

The angle by which the grater 17 can be rotated to adjust the temperature of the outflowing mixed water can be set in the following way:

Immediately adjacent to the outside of the groove 58 (in 4, above this), a further recess 65 is provided in the outer contour of the grater 17, but this has a larger diameter than the groove 58 and is not completely guided around the circumference of the grater 17. Rather, as can be seen in FIG. 6, a dovetail-shaped extension 66 projects radially outward from the “core” 67 of the grater 17. This dovetail-shaped projection 66 limits the rotatability of the grater 17 in FIG. 6 clockwise by coming into contact with the head of the screw 60.

An arcuate elongated hole 68 penetrates the wall between the annular shoulder, which is formed by the recess 65 against the portion of the grater 17 that supports the apron 20, and the outer end wall of the grater 17, which is surrounded by the apron 20, onto which the magnet coil 14 is also placed is. A screw 69 is guided through this slot 68 from the outside and holds a stop piece 70 on the ring shoulder of the recess 65 mentioned. The stop piece 70 extends radially from the "core" 67 of the grater 17 to the outer circumference of the annular shoulder formed by the recess 65. It limits the rotatability of the grater 17 counterclockwise by coming to bear against the head of the screw 60. The total angle of rotation through which the grater 17 can be seen is determined by the variable position of the stop piece 70 in the arcuate elongated hole 68.

When the grater 17 with the pilot-controlled valve 29 accommodated therein and the solenoid 14 actuating it is fixed by means of the U-shaped fastening part 59 and the screws 60 to 62 on the main housing 1, the housing 18 is pushed onto the apron 20 of the grater 17 and fastened there with a screw 19. A cylindrical collar 71 screwed to the housing 18, the could also be integral with the housing 18, engages in a groove in the right side surface of the main housing 1 in FIG. 1. In this respect, the conditions are identical to the way in which the outer housing 52 of the handle-like extension 6 on the left in FIG. 1 engages in a groove on the left side surface of the main housing 1.

Finally, the head of the screw 19 in the handle 18 is covered with a window 48, the appearance of which corresponds to the window 8 in the handle-like extension 6 on the left in FIG. Externally, as can be seen in FIG. 1, there is a completely symmetrical appearance.

The main housing 1 is fastened to the base part 2 by a central screw 72 (FIG. 2), the head of which lies in the upper region in the bore 25 already mentioned, which leads the mixed water flowing from the cylindrical chamber 21 to the outlet 3. The downward waterway is blocked in FIG. 2 by a sealing ring 73, which is arranged between the head of the screw 72 and the ring shoulder of the bore 25 below it.

To attach the outlet 3 to the main housing 1, a mounting piece 74 is screwed into the latter from above. The attachment piece 74 has a somewhat larger diameter in the upper region and here lies on the inner wall of the outlet 3 via O-rings. This is pushed over the attachment piece 74 to close to the upper end face of the main housing 1. A U-shaped fastening part 75 lies between the inner wall of the outlet 3 and the region of the fastening socket 74 which is reduced in diameter. The outlet 3 is fixed to it by means of a screw 76. The fastening part 75 bears with an axially extending projection 77 on an annular step which has the same diameter Connects wider area of the mounting piece 74 with the smaller diameter area. As a result, the outlet 3 is fixed in the axial direction. By appropriate profiling of the outer contour of the attachment piece 74, the axial projection 77 also acts as a limitation for the angle of rotation through which the outlet 3 can measure in relation to the main housing 1.

The exemplary embodiment described above concerned a contactlessly controlled, electrically operated mixer tap with a certain division of the various components into two handle-like approaches. The non-contact as well as this division are not necessary features of the invention.

Claims (9)

1. Sanitary mixing battery comprising a housing (1), an electrically operated valve (14) the closure elements (30, 34) of which control the outflowing mixed water, a regulating element (17) arranged in a chamber of the housing (1), which regulating element (17) determines the ratio of cold and hot water in the outflowing mixed water, and an outlet (3),
   characterised in that

   a) the regulating element is in the form of a hollow piston (17),

   b) the hollow piston (17) has on its outer periphery a structure (27) which, in cooperation with flow channels (22, 23) for cold and hot water which open into the housing chamber (21), determines the mixing ratio of that water;

   c) the path of the mixed water passes at least partially through the interior of the hollow piston (17) and at least the closure elements (30, 34) of the electrically operated valve (29, 14) are arranged in that region of the interior of the hollow piston (17).
2. Sanitary mixing battery according to claim 1, characterised in that there is formed on the hollow piston (17) a cylindrical skirt (20) to which an operating grip (18) may be fastened.
3. Sanitary mixing battery according to claim 1, in which the electrically operated valve comprises a magnetizing coil, characterised in that the magnetizing coil (14) is arranged in the space surrounded by the skirt (20) of the hollow piston (17).
4. Sanitary mixing battery according to any one of the preceding claims, characterised in that the structure on the outer periphery of the hollow piston (17) comprises a groove (27) which conducts the mixed water along the outside of the hollow piston (17).
5. Sanitary mixing battery according to claim 4, characterised in that the groove (27) conveys the mixed water to the open end of the hollow piston (17).
6. Sanitary mixing battery according to any one of the preceding claims, in which the regulating element is in the form of a rotary piston, characterised in that the groove (27) is guided along the outer periphery of the hollow piston (17) in a helical manner at an angle to the axis, and the middle points of the outlet openings of the flow channels (22, 23) for cold and hot water into the housing chamber (21) lie in a straight line which is parallel to the rotational axis of the hollow piston (17).
7. Sanitary mixing battery according to claim 3, in which the electrically operated valve is a pilot-controlled valve comprising as the closure element a flexible diaphragm which is able to move back and forth between an open position and a closed position under the effect of the pressures prevailing on its two sides, wherein a closure body which is displaceable by the magnetizing coil influences the pressures on both sides of the diaphragm by opening and closing a pilot opening, characterised in that the closure body (42) and the pilot opening (41) are arranged remote from the diaphragm (30) in the vicinity of the magnetizing coil (14), a first channel (43) leads from the pilot opening (41) through a solid region of the hollow piston (17) into a space (44) in which the pressure prevailing on one side of the diaphragm (30) is present, and a second channel (39) leads from the space (40), which, after the lifting of the closure body (42) from the pilot opening (41), is in communication with the first channel (43), through a solid region of the hollow piston (17) into a space in which the pressure prevailing on the other side of the diaphragm (30) is present.
8. Sanitary mixing battery according to any one of the preceding claims, characterised in that the closure elements of the electrically operated valve (29, 14) comprise:

   a) a tubular, flexible diaphragm (30) which is fixed at its ends to the inside wall of the hollow piston (17) and is radially movable in the middle region;

   b) an abutment body (34) which is arranged inside the tubular, flexible diaphragm (30) and against the generated surface of which the diaphragm (30) rests in the closed position and from the generated surface of which the diaphragm (30) lifts in the open position.
9. Sanitary mixing battery according to claim 8, characterised in that the abutment body (34) is part of a cage (31) holding the diaphragm (30), which cage has at each axial end a supporting ring (35, 36) which cooperates with a radial bead (32, 33) at the corresponding axial end of the diaphragm (30), the two supporting rings (35, 36) being joined to the abutment body (34) via ribs (37).

Images